1. Field of the Invention
The present invention relates to a machine learning apparatus for learning a condition for starting laser machining, and to a laser apparatus and a machine learning method. More particularly, the invention relates to a machine learning apparatus that learns light output command data for starting laser machining of a workpiece without causing damage to a laser oscillator or a laser optical system due to reflected laser beam or causing stoppage of laser oscillation due to generation of an alarm, and to a laser apparatus and a machine learning method.
2. Description of the Related Art
Since prevention of damage to a laser oscillator or a laser optical system due to reflected light is an important issue in designing a laser apparatus, a variety of related techniques have been reported.
For example, Japanese Unexamined Patent Publication No. 2007-30032 discloses a technique for monitoring whether the surface state of a workpiece is normal or not by using a laser light measuring unit and a reflected light measuring unit. Further, Japanese Unexamined Patent Publication No. 2007-42981 discloses an optical-fiber laser equipped with a pump-light source control means for preventing amplification of returned light by reducing the output of the pump-light source when the intensity of the returned light exceeds a predetermined value.
Further, Japanese Unexamined Patent Publication No. H11-170074 discloses a laser machining apparatus which is equipped with a reflected light detector and a reflected light intensity calculating unit for calculating reflected light intensity immediately after reflection by using a reflected light distribution table, and which controls a laser oscillator based on a comparison made between the reflected light intensity calculated by the reflected light intensity calculating unit and its reference value. Further, Japanese Unexamined Patent Publication No. 2000-126880 discloses a laser machining apparatus which controls laser beam based on a comparison made between the amount of increase in reflected light intensity, mathematically obtained from the reflected light intensity, and a predetermined reference value.